Due to the recent development of digital technology and mobile communication technology, a user can carry mobile devices, for example, a smartphone, a tablet, a PC, a notebook, and the like, and use the mobile devices anywhere. These mobile devices basically have the function that can store music files and reproduce the stored music files.
Recently, various speaker devices and headset devices, which receive and output music files reproduced in mobile devices by using, for example, Bluetooth wireless communication, have been developed, manufactured, and distributed. In particular, the speaker device is called a Bluetooth speaker device and has an advantage that most users can carry the speaker device and enjoy music at a desired place according to life patterns of the users who enjoy many outdoor activities.
Bluetooth is a protocol for standard short-range wireless communication, and the Bluetooth device is commonly recognized and connected between two devices through a series of operations, such as pairing with the mobile device, mutually transmits various signals via a Bluetooth communication network.
However, most Bluetooth speaker devices have better sound quality than speaker devices of the mobile devices, but are much lower than high-power speaker devices present in a home or other places. As the users desire to enjoy music files stored in the mobile devices with better sound quality, the users try to find speaker devices with better sound quality. Therefore, there is a need for a new type of Bluetooth speaker device that can satisfy the user's demand.